Figure 3. ROS signaling in physiology.

(a) ROS have recently been discovered as second-messenger signaling agents used to control growth and maintenance of neural stem cells located in both the subgranular zone of the hippocampus as well as the subventricular zone of the lateral ventricles. (b) ROS have also been discovered as signaling agents at both the biochemical and whole-organism level to trigger chemotaxis and recruitment of leukocytes to damaged tissue. (c) Finally, the oxidation state of peroxiredoxins (Prx) have been shown to be modulated between reduced (Prx-SH) and oxidized (Prx-SO₂H) forms to regulate circadian rhythms in the absence of transcription or translation.